Table 3

Lung cancer risk^a associated with cigarette smoking by GSTM1 genotype according to intervention group, ATBC Study, Finnish men

Group	Genotype	Years of smoking tertile					P-trend^b
				<37	37–42	>42
				OR (95% CI)^a No. of cases/controls	OR (95% CI)^a No. of cases/controls	OR (95% CI)^a No. of cases/controls
All subjects	GSTM1 present	1.00 (reference)	1.15 (0.62–2.14)	1.85 (0.85–4.02)	0.002
		41/52	56/65	54/62
	GSTM1 null	1.00 (reference)	3.77 (1.98–7.16)	6.28 (2.70–14.63)	0.0001
		33/69	53/44	69/49
α-Tocopherol
NO	GSTM1 present	1.00 (reference)	2.41 (0.98–5.92)	2.37 (0.79–7.15)	0.003
		18/31	29/24	28/29
	GSTM1 null	1.00 (reference)	6.78 (2.69–17.11)	21.15 (6.26–72.69)	0.0001
		13/44	35/29	45/21
YES	GSTM1 present	1.00 (reference)	0.60 (0.24–1.46)	1.33 (0.43–4.18)	0.29
		23/21	27/41	34/25
	GSTM1 null	1.00 (reference)	2.20 (0.85–5.74)	1.34 (0.36–5.03)	0.28
			20/25	23/15	24/28
β-carotene
NO	GSTM1 present	1.00 (reference)	1.19 (0.48–2.92)	1.19 (0.40–3.58)	0.22
		18/22	29/28	26/24
	GSTM1 null	1.00 (reference)	3.38 (1.32–8.66)	8.17 (2.24–29.82)	0.004
		20/39	22/22	27/21
YES	GSTM1 present	1.00 (reference)	1.35 (0.56–3.26)	3.56 (1.14–11.12)	0.001
		23/30	27/37	36/30
	GSTM1 null	1.00 (reference)	4.78 (1.91–11.92)	6.01 (1.90–19.08)	0.001
		13/30	36/22	42/28

^a OR and 95% CI after adjusting for age, daily cigarettes smoked, and intervention assignment.
^b P for trend based upon the P (two-sided) of years smoked modeled as a continuous term.